<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <script src="../../vue.js"></script>
  </head>
  <body>
    <div id="app">
      <App></App>
    </div>
    <script>
      Vue.config.productionTip = false;
      const Header = Vue.extend({
        name: "Header",
        template: `<h2>我是头部header</h2>`,
      });

      const App = Vue.extend({
        name: "App",
        components: {
          Header,
        },
        template: `<div>
                <h1>App {{message}}</h1>
                <Header></Header>
                </div>`,
        data() {
          return {
            message: "hello",
          };
        },
      });
      console.log(App, "App"); //VueComponent构造函数
      const vm = Vue({
        el: "#app",
        components: {
          App,
        },
        data() {
          return {};
        },
      });
    </script>
  </body>
</html>
